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Abstract: The objective of this study was to develop a new class of bimetallic ZnO/Ag embedded polyurethane multi-functional nanocomposite by a straightforward approach. Bimetallic nanomaterials, composed of two unlike metal elements, are of greater interest than the monometallic materials because of their improved characteristics. In the present study the bimetallic composite was prepared using sol–gel via the facile electrospinning technique. The utilized sol–gel was composed of zinc oxide, silver and poly(urethane). The physicochemical properties of as-spun composite mats were determined by X-ray diffraction pattern, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and transmission electron microscopy. The antibacterial activity was tested using Escherichia coli as model organism. The antibacterial test showed that ZnO:Ag/polyurethane composite possesses superior antimicrobial activity than pristine PU and ZnO/PU hybrids. Furthermore, our results illustrate that the synergistic effect of ZnO and Ag resulted in the advanced antimicrobial action of bimetallic ZnO/Ag composite mat. The viability and proliferation properties of NIH 3T3 mouse fibroblast cells on the ZnO:Ag/polyurethane composite nanofibers were analyzed by in vitro cell compatibility test. Our results indicated the non-cytotoxic behavior of bimetallic ZnO:Ag/polyurethane nanofibers towards the fibroblast cell culture. In summary, novel ZnO:Ag/polyurethane composite nanofibers which possess large surface to volume ratio with excellent antimicrobial activity were fabricated. The unique combination of ZnO and Ag nanoparticles displayed potent bactericidal effect due to a synergism. Hence the electrospun bimetallic composite indicates the huge potential in water filtration, clinical and biomedical applications. [Copyright &y& Elsevier]

Abstract: In the current study, we aimed to represent a straightforward approach to fabricate novel CuO/TiO2 composite nanorods by an electrospinning process using copper nitrate and titanium isopropoxide as precursors for copper oxide and titanium oxide respectively; the obtained electrospun nanorods were vacuum dried at 80°C and then calcined at 600°C. Model microorganisms Escherichia coli KCCM 11234 and Staphylococcus aureus KCCM 11256 had been used to check the antimicrobial efficacy of electrospun nanorods. The antibacterial activity and the interaction mechanism of CuO/TiO2 composite nanorods against bacteria were investigated by minimum inhibitory concentration (MIC) method and analyzing the morphology of the bacterial cells following the treatment with nanorods solution. CuO/TiO2 composite nanorods have diameter of 100nm and average lengths of one micrometer. The elemental analysis using EDX and EPMA confirms the presence of Cu atoms in CuO/TiO2 composite nanorods. Results showed that doping promotes the antimicrobial effect and prepared nanorods possess excellent antibacterial abilities under visible light. As a result, our study for the first time highlights the potential of copper oxide to augment the bactericidal efficacy and hence can be used in the manufacture of medical appliances. [Copyright &y& Elsevier]